Acne may get worse while on the drug but then improve but the derms will keep you on it aslong as they think you need it and that will be until the acne cures so it may take 3 months to clear if your lucky or you may need to be on it for say 6 months or longer it all depends on how your body reacts to the drug.

What i know is that they say people with acne have a disease in there oil glands where more bacteria than usual is being produced evne though everyone has bacteria in there oil glands but people with acne normally have over reactive oil glands pumping more oil to the surface of the skin or the oil gets clogged under bloked pores and forms nasty spots. So the drug works directly on the oil glands and trys to control them thats why it make take time.